I think you would be better off paying cash than going through insurance as I would consider this a minor repair. You would have to pay a deducible and your premium would go up next year if you went through insurance. Better trade-off by paying cash in this situation in my opinion.
In terms of body shops in Markham I have heard good things about Chipmaster Markham (located across Markville Mall).
If you look at their ‘Before and After’ section of their website there is a white BMW which has similar damage to yours. They are offering some sort of group buy on RedFlagDeals which you can read and it with give you a lot of positive feedback from previous customers having their car repaired by them.